安徽宣城风成沉积—红土系列剖面ESR年代学研究

ESR DATING OF EOLIAN SEDIMENT AND RED EARTH SERIES FROM XUANCHENG PROFILE IN ANHUI PROVINCE

To elucidate the chronological characteristics of the Xuancheng profile in Anhui Province,the ESR ages of 10 samples were determined.The results indicated that the ESR age increased with the increase of stratum depth and followed the stratigraphic sequence.If taking the Brunhes-Matuyama boundary (B/M) (730ka) between early and middle Pleistocene,based on previcus researches and our ESR dating results,the gravel layer and the upper silt layer could be assigned to the later stage of early Pleistocene epoch(1000-730ka),Plinthitic red earth layers and-brown-yellow eolian sediment layers (from the 15th layer to the 6th) to the early stage of middle Pleistocene epoch (730-400ka),and the isotropic red earth (from the 5th layer to the 3rd) to the later stage of middle Pleistocene epoch (400-100ka).